Tool holders



J1me 1961 LE ROY J. WENDLING 2,987,334

TOOL HOLDERS Filed June 22, 1959 I n n as 42 44 2o 25 8 A F|G'5 3 1/} 56 l l 4 /j x s! 'Z as 68 -70 I 66 INVENTOR. 50 LEROY J. WENDLING ATTORNEYS United States Patent 6 2,987,334 TOOL HOLDERS Le Roy J. Wendling, Dayton, Ohio, assignor to The Apex Machine & Tool Company, Dayton, Ohio, at corporation of Ohio Filed June 22, 1959, Ser. No. 821,942 6 Claims. (Cl. 287-119) This invention relates to coupling devices, and more particularly to coupling devices for tools and tool holding devices incorporating an interlock construction for retaining a driven element in working relation with a driving element.

It is a primary object of the present invention to provide a coupling device of novel characteristics wherein the component parts are constructed for driving interengagement and wherein these parts also incorporate an interlock mechanism which positively prevents accidental disengagement thereof.

An additional object of the invention is to provide a coupling device for tools and tool holders including an interlocking mechanism resistant to shock and disengaging forces caused by the impact of a power driven tool.

A further object of the invention is to provide a tool holder as outlined above which is of rugged and relatively inexpensive construction as well as easy to operate.

Other objects and advantages of this invention will be apparent from the following description, the accompanying drawing and the appended claims.

In the drawing FIG. 1 is an exploded perspective view showing a tool holder and tool constructed in accordance with the invention;

FIG. 2 is an axial section, taken on the line 22 of FIG. 3, showing the tool holder and tool of FIG. 1 in assembled and interlocked relation;

FIG. 3 is a section on the line 33 of FIG. 2;

FIG. 4 is a fragmentary view similar to FIG. 2 illustrating the operation of releasing the interlock between the tool and tool holder for removal of the tool; and

FIG. 5 is a fragmentary view showing a modified form of the invention as applied to splined connections.

Referring to the drawing, which illustrates preferred embodiments of the invention, the tool holder is indicated generally at and the tool at 11, and the tool 11 is illustrated as a socket wrench for the use with hexagonal bolt heads or nuts as shown by the hexagonal socket 12 at the working end of the tool 11. The tool holder 10 includes a body portion 13 which is constructed for attachment to a desired driver, as shown by the square socket 14 for engagement by a square driving spindle shown fragmentarily at 15 in FIG. 2. The socket 14 is provided with a transverse bore 16 to receive a retaining pin 17 for holding the tool holder on the spindle 15, and the circumferential groove 18 on the body portion 11 in turn receives a snap ring 19 for retaining the pin 17 in operative position. This portion of the tool holder is subject to wide variation as desired to fit other drivers without affecting the interlock mechanism of the invention between the tool holder 10 and the tool 11 as now described.

The tool holder 11 is of tubular construction throughout, and it is provided at its driven end with a square socket 29 proportioned for driving engagement by the square shank 22 which projects from the body portion 13 of the tool holder. The portion 23 of the inner surface of the tool 11 intermediate the sockets 12 and represents a cylindrical working clearance for machining purposes and is not otherwise related to the invention,

2,987,334 Patented June 6, 1961 which is directed particularly to the interlock mechanism between the shank 22 and socket 20.

Referring particularly to FIGS. 2 and 3, the interlock mechanism includes a ball 25 and cooperating plunger 30 carried by the shank 22. The plunger 30 is mounted for reciprocating movement in an axial bore 31 extending from the outer end of the shank 22 by stopping short of the socket 14. The plunger 30 is normally urged by a coil spring 33 toward an outer limit position established by a suitable retaining means illustrated by the snap ring 34, and it is movable against the spring 33 to an inner limit position established by engagement of its inner end with the annular shoulder 35 adjacent the inner end of the bore 31.

The ball 25 is located in a bore 40 which extends radially through the shank 22 but has one end sufl'lciently reduced in cross section at 41 to limit the projection of the ball 25 therefrom. The other end of the bore 40 may be left open for initial assembly of the ball 25, since thereafter the ball is held between the bore 31 and the end 41 of the bore 40 by the plunger 30.

The plunger 30 is provided with a shallow circumferential groove 42 into which a portion of the ball 25 normally restswhen the plunger is in the outer limit position. With the plunger 30 in this position, the ball 25 is held in an outwardly projecting position in relation to the shank 22. The coupling includes ball retracting means including a second ball receiving circumferential depression or groove 43 cut substantially deeper into the plunger 30 and in axially spaced relation outwardly of the groove 42. The dimension of the groove 43 is such that when the plunger'30 is depressed against the spring 33 to its inner limit position, the ball 25 is free to drop inwardly into the groove 43 so that it no longer projects from the shank 22. Sufficient clearance is provided between the restricting end portion 41 and the projecting ball 25 when the ball is in its normal position within the shallow groove 42 and to permit the axial movement of the plunger 30 under or past the ball 25.

The ball 25 cooperates in interlocking relation with one of a series of grooves 44 forming recesses in the side walls of the tool socket 20, and while only one of these grooves is used at a time, it is simpler to provide one in each wall since this eliminates the necessity for a specific angular alignment of the tool and the tool holder during assembly. The manner of assembly and interlocking of the tool and tool holder, as well as the manner of their release, is illustrated in FIG. 4. In the normal condition of the parts, the ball 25 will project from the shank 22 to limit insertion of the shank in the socket .20 by abutment of the ball with the end of the socket. The operator accordingly inserts a screwdriver, punch or similar implement such as shown at 45 in FIG. 4 through the interior of the tool 11 and presses the plunger 30 against the spring 33 to its inner limit position wherein the ball 25 is retracted as shown in FIG. 4. The shank 22 can then complete its entry'into the socket 20, and after the implement 45 is withdrawn, the spring 33 will return the plunger 30 to its position shown in FIG. 2 wherein it forces the ball 25 outwardly into projecting and interlocked relation with the adjacent groove 44. V

Positive locking against accidental removal of the tool 11 is assured in that any outward pull on the tool 11 tending to disengage it from the shank 22 also causes the ball 25 to be cammed inwardly against the groove 42. The plunger 30 is therefore locked against disengaging inward movement until the force tending to remove the tool 11' is relieved. In addition, the construction of the plunger. 30 with the circumferential groove 43 minimizes the possi:

bility of accidental release of the locking mechanism as a result of the shock forces incident to use, since the plunger can respond to such shock forces by rotating in the bore 31 rather than tending to vibrate in an axial direction as would tend to occur if the plunger were held against such rotational movement. This interlock construction is therefore simple to manufacture and to use, and it provides positive assurance against accidental disconnection of the parts in use. At the same time, when it is necessary to change the tool, this is quickly and easily done by reinserting of the implement 45 in the manner shown in FIG. 4, whereupon the tool can he slipped off the shank for replacement.

FIG. shows a tool and tool holder combination which is similar in operating characteristics to the combination described in connection with FIGS. 1-4 and differs primarily in the use of asplined driving connection between the tool and tool holder. In addition, FIG. 5 illustrates the application of the invention to a direct connection between the drive spindle of a power tool and a driven member. Thus in FIG. 5, the tool holder 50 and tool 51 are connected by interlocked couplings in accordance with the invention, and the tool holder 50 is connected at its driven end through a universal indicated generally at 53 to an adaptor 55 which is in turn similarly coupled with the power drive spindle 5 6.

The driving end of the tool holder 50 includes splines 60 for. driving engagement with complementary splines 61 which define a socket in the driven end of the tool 51, and an annular shoulder 62 within the tool 51 limits telescoping engagement of the tool holder 50 therein. FIG. 5 also shows the splines 61 terminating short of the shoulder 62 to leave a circumferential clearance 63 which forms a recess similar to the grooves 44 in the tool 11. The driving end of the tool 51 is shown at 64 as essentially the same as the end portion 12 of the tool 11.

The interior of the tool holder 50 is constructed similarly to the shank 22 of the tool holder to receive a plunger 65 and spring 66 similar in function to the plunger 30 and spring 33, and the plunger 65 is retained within the bore 67 in the tool holder 50 by a snap ring 68. The plunger 65 includes a portion 70 at its outer end which is of reduced diameter to form in efiect a depression or groove comparable in function to the groove 43 in the plunger 30. An additional shallow groove 71 in the plunger 65 corresponds in location and function to the groove 42 in the plunger 30.

The tool holder 50 is provided with a radial bore 74 for receiving a locking member 75 corresponding in function to the ball but in the form of a pin rather than a ball due to the increased radial dimensions of the splined tool holder 50 in comparison with the square shank 22 on the tool holder 10. The pin 75 is provided with spherically curved ends for cooperation with the grooves 70 and 71 and for projection outwardly of the tool holder 50 respectively, and the outer end of the bore 74 is restricted at 76 to limit projection of the pin 75 therefrom. Otherwise, the pin 75 cooperates with the plunger 65 in the same manner as the ball 25 with the plunger 30, and in its locking position, the outer end of the pin 75 engages in the recess 63 as shown in FIG. 5.

The power drive spindle 56 is shown as identical in construction with the driving end of the tool holder 50, and it incorporates similar splines 80 and locking parts which are identified as 65', 75' and so forth. The driven end of the adaptor 55 is similarly shown as identical with the driven end of the tool 51 to include splines 81 and an annular shoulder 82 for engagement with the splines 80, and the splines 81 terminate short of the shoulder 82 to provide a recess 83 for engagement by the pin 75'. Since the driving end of the adaptor 55 is closed by the universal 53, however, a passage 85 is provided in the adaptor 55 which leads generallylongitudinally thereof from its outside surface to the inner end of the socket portion thereof for receiving an implement for eifecting release of the v 4 i plunger 65 in the same manner as described in connection with FIG. 4 and as illustrated in dotted lines at 88.

While the forms of apparatus herein described constitute preferred embodiments of the invention, it is to be understood that this invention is not limited to these precise forms of apparatus and that changes may be made therein without departing from the scope of the invention which is defined in the appended claims.

What is claimed is:

1. A tool holder for a tool having a socket at the mounting end thereof provided with a recess in the wall thereof, comprising a shank adapted for driving engagement within said socket and having a longitudinal passage of circular section therein open at the outer end thereof, a plunger supported for axial and rotational movement within said passage, means in said shank defining inner and outer limit positions for said plunger, means biasing said plunger to said outer limit position, a locking member mounted for transverse movement in said shank between a position projecting laterally from said shank for locking engagement with the tool recess and a retracted position, means on said plunger for holding said locking member in said projecting position in said outer limit position of said plunger, said plunger including a circumferentially relieved portion for receiving said locking member in said inner limit position of said plunger to provide for retraction of said locking member out of engagement with said recess, and said plunger having an end portion accessible through said outer end of said passage by an implement for moving said plunger against said biasing means to said inner limit position to retract said locking member.

2. A tool holder for a tool having a socket at the mounting end thereof provided with a recess in the wall thereof, comprising a shank adapted for driving engagement within said socket and having a longitudinal passage therein open at the outer end thereof, a plunger supported for axial movement within said passage, means in said shank defining inner and outer limit positions for said plunger, means biasing said plunger to said outer limit position, a locking member mounted for transverse movement in said shank between a position projecting laterally from said shank for locking engagement with the tool recess and a retracted position, a relatively shallow circumferential groove on said plunger positioned for receiving said locking member with said plunger in said outer limit position for holding said member in said projected position and preventing shock depression of said plunger tend ing to disengage said tool upon impact, said plunger having a circumferential depression in axially spaced relation to said groove'for receiving said member upon the depression of said plunger into said inner limit position to provide for the retraction of said locking member out of engagement with said socket, and said plunger being accessible through said outer end of said passage by an implement for moving said plunger against said biasing means to said inner limit position.

3. A tool holder for a tool having a socket at the mounting end thereof provided with a recess in the wall thereof, comprising a shank adapted for driving engagement within said socket and having a longitudinal passage therein open at the outer end thereof, a plunger supported for axial movement within said passage, means in said shank defining inner and outer limit positions for said plunger, means biasing said plunger to said outer limit position, a locking member having an inner spherical portion for coaction with said plunger and mounted for transverse movement in said shank between a position projecting laterally from said shank for locking engagement with the tool recess and a retracted position, a relatively shallow circumferential groove on said plunger positioned for receiving said spherical portion with said plunger in said outer limit position for holding said member in said projected position and preventing shock depression of said plunger tending to disengage said tool upon impact, said plunger having a circumferential depression in axially spaced relation to said groove for receiving said member upon the depression of said plunger into said inner limit position to provide for the retraction of said locking member out of engagement with said socket, and said plunger being accessible through said outer end of said passage by an implement for moving said plunger against said biasing means to said inner limit position.

4. A tool holder for a tool having a socket at the mounting end thereof provided with a recess in the wall thereof, comprising a shank adapted for driving engagement within said socket, said shank having a longitudinal passage therein open at the outer end thereof and a guideway therein leading radially from said passage to the outside thereof, a plunger supported for axial movement within said passage, means in said shank defining inner and outer limit positions for said plunger, means biasing said plunger to said outer limit position, a ball mounted for movement in said guideway between a position projecting laterally fi'om said shank for locking engagement with the tool recess and a retracted position, said plunger being proportioned to hold said ball in said projecting position in said outer limit position of said plunger, said plunger including a depression for receiving said ball in said inner limit position of said plunger to provide for retraction of said ball out of engagement with said recess, and said plunger being accessible through said outer end of said passage by an implement for moving said plunger against said biasing means to said inner limit position.

5. A tool holder for use in combination with a tool having a socket at the mounting end thereof and provided with a recess in the wall thereof, comprising a tool holder including a shank adapted for driving engagement within the tool socket, said shank having a longitudinal passage therein open at the outer end thereof and a guideway therein leading radially from said passage to the outside thereof, a plunger supported for axial movement within said passage, means in said shank defining inner and outer limit positions for said plunger, means biasing said plunger to said outer limit position, a pin having an inner spherical end mounted for radial movement in said guideway between a position projecting laterally from said shank for locking engagement with the tool recess and a retracted position, said plunger having a groove for receiving the 6 l spherical and of said pin to hold said pin in said projecting position in said outer limit position of said plunger, said plunger including a circumferential depression for receiving said inner end of said pin in said inner limit position of said plunger to provide for retraction of said pin out of engagement with said recess, and said plunger being accessible through said outer end of said passage by an implement for moving said plunger against said biasing means to said inner limit position.

6. A tool holder for use in combination with a tool having a socket at the mounting end thereof provided with a recess in the wall thereof, said tool holder comprising a shank adapted for driving engagement within the tool socket, said shank having a longitudinal passage therein and a guideway leading transversely from said passage to the outside thereof, a plunger supported for axial movement within said passage, means in said shank defining inner and outer limit positions for said plunger, means biasing said plunger to said outer limit position, a locking member mounted for movement in said guideway between a retracted position and a position projecting laterally from said shank for locking engagement in the recess in the tool socket preventing movement of the tool axially of said shank, said plunger having a first and relatively shallow depression for holding said locking member in said projecting position in said outer limit position of said plunger, said plunger further including a second depression deeper than said first depression for receiving said locking member in said inner limit position of said plunger to provide for retraction of said locking member out of engagement with the tool, and said passage being open at the outer end thereof for access to said plunger by an implement through the tool for moving said plunger against said biasing means to said inner limit position.

References Cited in the file of this patent UNITED STATES PATENTS 1,864,466 Peterson June 21, 1932 2,549,397 Sparks Apr. 17, 1951 2,601,389 Guelph Jan. 24, 1952 2,721,090 Kaman Oct. 18, 1955 2,954,994 Beers Oct. 4, 1960 

